Tension headache: This is often the most common cause of scalp tenderness, typically presenting with bilateral scalp pain and tenderness, often accompanied by headache.

Migraine: Similar to tension headaches but usually involves unilateral pain and can be accompanied by other symptoms like nausea, vomiting, and sensitivity to light and sound.
Scalp dermatitis: Inflammation of the skin on the scalp can cause tenderness, itching, and redness, often due to allergic reactions, irritants, or conditions like psoriasis.
Scalp folliculitis: An inflammatory condition affecting the hair follicles, leading to tenderness, redness, and sometimes pus-filled bumps on the scalp.
Trauma: Direct injury to the scalp can cause tenderness, swelling, and sometimes lacerations.

Temporal arteritis (Giant Cell Arteritis): Although less common, this condition is critical to diagnose due to the risk of blindness and other serious complications. It typically presents with unilateral scalp tenderness, jaw claudication, and visual disturbances in individuals over 50 years old.
Meningitis: Infection of the meninges can cause scalp tenderness along with fever, headache, stiff neck, and altered mental status. Early diagnosis is crucial for effective treatment.
Subgaleal hematoma: A collection of blood beneath the galea aponeurotica, a tough fibrous layer of the scalp, which can occur after trauma. It's a serious condition that requires prompt medical attention.

Trichodynia: A condition characterized by painful scalp in association with hair loss, often seen in patients with androgenetic alopecia or telogen effluvium.
Neurological disorders: Certain conditions like trigeminal neuralgia or occipital neuralgia can cause scalp tenderness, usually described as sharp, stabbing pains.
Infections: Less common infections such as scalp abscesses or osteomyelitis of the skull can cause localized tenderness and require specific treatments.